Only for information purpose, this on old pc with Vs2015. It doesnot compile.
From the screenshot, you do not have the build method set for the project. Hard to say how that could happened. You should be able to resolve it by invoking "Setup / Automatic build methods setup" and then clicking the left button on build "ComboBox" in the toolbar that has left and right down arrows...
Also, at this time, with next major release immininent, I recommend downloading the latest nightly build and overcome somehow mcaffee false alarm. Latest builds come with clang compiler, which is good enough for any real work (no need to meddle with MSC15 anymore).